Alice

Do I have this correct?

The "Living Next Door to Alice" was originally released in 1972 but it's the Smokie 1976 version we all know.

However, the one we actually know and sing along to is a later version, "Alice, who the fuck is Alice!?", which I always thought was Roy "Chubby" Brown:

Ooooooooh ...

Smokie collaborated on a novelty re-recording in 1995 with comedian Roy Chubby Brown, with the song interspersed with Roy Chubby Brown saying "Who the fuck is Alice?".

 So it's both Smokie AND Roy "Chubby" Brown, got it.